A man has been arrested following a “critical incident” at a house in Killygordan overnight.
Gardai were called to what was described as a domestic situation at Forest Park.
Gardai then sealed off the area.
Eye-witnesses have told how three ambulances arrived at the scene just after 7am.
A number of occupants including children were also seen leaving the house a short time later.
Gardai are saying nothing more at this stage but a full investigation has been launched.
Local county councillor Patrick McGowan said “All we know is that there has been a very serious incident and everyone in the locality is shocked.
“I’m not sure who lives in the house because this housing estate was built relatively late ion the Celtic Tiger era and there are a lot of people from outside the area renting there.
“All we know is that somebody has been seriously hurt and Gardai are awaiting the forensics team to arrive.”